The present invention is directed toward a device for protecting pilings and similar structures mounted in water from damage due to ice uplift.
As is well known in the art, severe damage can be caused to docks and similar structures as a result of the uplifting of the support piles in the winter months. This results from the ice which forms near the upper surface of the water and which surrouds the pilings and becomes tightly affixed thereto. As the tide rises, the ice mass that has formed around the piling rises carrying the piling upwardly therewith. It is not uncommon for the pilings to be moved several feet and the same can actually be removed from the hole into which it had been supported. This movement and dislodgment of the pilings has the even more significant consequence of seriously damaging the docks and other structures which are being supported causing expensive and time-consuming annual repairs.
Attempts have been made in the past to prevent such uplifting of pilings. For example, U.S. Pat. Nos. 4,114,388 and 4,252,471 show frusto-conically shaped guard members which are intended to be securely fastened to the pilings at the water level. Should ice form around the guard member and then be moved upwardly by the rising tides, the ice should simply slide upwardly across the guard member in view of the reduced diameter thereof.
Such devices should, theoretically, provide some protection. However, since they must be permanently secured to the pilings, they are relatively expensive to install. Furthermore, in the event that the relatively thin outer wall of the guard member ever becomes deformed or if a hole should ever be formed therein, ice could securely fasten itself thereto and not slide off of the guard member as intended. Such deformation of the guard member is not unlikely since the same can be easily hit by boats or the like.
Other devices for preventing uplifting of pilings have also been proposed. For example, the devices shown in U.S. Pat. Nos. 3,170,299 and 3,370,432 are sleeves which have an inner diameter slightly greater than the outer diameter of the pilings and which are intended to surround the same. The sleeves are buoyant and move up and down with the water line as the tide rises and lowers.
Each of these two patents includes means for preventing ice from forming in the annular gap between the sleeve and the piling. There is, however, no assurance that such result can be obtained. Furthermore, the device shown in U.S. Pat. No. 3,370,432 must be frequently checked to ensure the proper amount of antifreeze which is placed in the annular gap.
Another prior art device which is structurally somewhat similar to the device shown in U.S. Pat. No. 3,370,432 is illustrated in U.S. Pat. No. 934,176. This patent is also directed toward a sleeve which surrounds a piling and includes an annular gap. The device is not specifically intended to prevent movement due to ice uplifting but, rather, includes a preservative solution in the annular gap so that as the tide rises and lowers, the solution is constantly applied to the piling.